from
The Collaborative International Dictionary of English v.0.48
Gnaw \Gnaw\ (n[add]), v. t. [imp. & p. p. {Gnawed} (n[add]d); p.
pr. & vb. n. {Gnawing}.] [OE. gnawen, AS. gnagan; akin to D.
knagen, OHG. gnagan, nagan, G. nagen, Icel. & Sw. gnaga, Dan.
gnave, nage. Cf. {Nag} to tease.]
1. To bite, as something hard or tough, which is not readily
separated or crushed; to bite off little by little, with
effort; to wear or eat away by scraping or continuous
biting with the teeth; to nibble at.
[1913 Webster]
His bones clean picked; his very bones they gnaw.
--Dryden.
[1913 Webster]
2. To bite in agony or rage.
[1913 Webster]
They gnawed their tongues for pain. --Rev. xvi.
10.
[1913 Webster]
3. To corrode; to fret away; to waste.
[1913 Webster]
4. To trouble in a constant manner; to plague; to worry; to
vex; -- usually used with at; as, his mounting debts
gnawed at him.
[PJC]